Asteroids are ancient space rocks left over from the formation of the Solar System. They are thought to have brought complex molecules, and possibly early life, to Earth billions of years ago. Today, our planet's current inhabitants must learn how to keep themselves safe from any future impacts.
Through ESA’s planetary defence efforts, Europe is a fundamental contributor to a global planetary defence system that is capable of providing early warning of dangerous near-Earth objects (NEOs) larger in size, about three weeks in advance, and able to deflect asteroids smaller than 1 km if known more than two years in advance.
